In surgical procedures, a medical stapler may be used for suturing a living organism that has been cut open. A medical stapler disclosed in Patent Document 1 is constituted by a housing, a lever, which is rotatably attached to the housing, and a magazine, which is attached to the housing in a detachable manner and stores multiple staples. FIG. 6 illustrate a conventional medical stapler, wherein FIG. 6(a) is a side view of the entirety and FIG. 6(b) is a side view of a magazine. Note that while the conventional medical stapler 20 shown in FIG. 6(a) has a lever 3 rotatably attached to a housing 1, there are staplers having the magazine 2 and the lever 3 connected rotatably and attached to the housing 1.
The magazine 2 includes an anvil, which is formed by making a front edge of a rail secured in the magazine 2 thin and bending it, a ram, which is arranged in a movable manner to and back from the front edge of the anvil, and a biasing member, which biases the ram in a direction away from the front edge of the anvil. A predetermined number of staples are aligned on the rail, and these staples are then biased by an elastic member toward the anvil at the edge of the rail.
The staples are formed by bending a rounded, stainless-steel wire rod into a U shape, and are formed having pointed legs so as to reduce resistance when both end portions pierce through a living organism. By applying pressure on the lever 3, the ram is driven and lowered by the lever 3 so that the edge of the ram makes contact with the staples held on the anvil. If pressure is further applied on the lever 3 to lower the ram, the staples are bent into a quadrangular shape, so that they can suture a living organism.
The housing 1 and the lever 3 are made of synthetic resin, such as ABS resin, and formed into shapes in consideration of gripping ease and user-friendliness. Moreover, the magazine 2 is generally formed using transparent ABS resin, which allows external confirmation of the remaining number of the staples stored therewithin.
Connection of the magazine 2 and the housing 1 of such a conventional stapler 20 is established by fitting together a latching convexity 2b provided in the magazine 2 and a latching concavity 1b provided in the housing 1. Here, the conventional latching concavity 1b and latching convexity 2b have linear shapes as illustrated and are provided in parallel along the length of the rail on which the staples are deployed.
Since if the connection between the housing 1 and the magazine 2 loosens, they may easily disconnect from each other, thickness of the magazine 2 is formed so as to settle perfectly within the width between the inner surfaces of the housing 1, thereby further increasing rigidity of the housing 1. As a result, the latching convexity 2b projects out from the width between the inner surfaces of the housing 1, and thus connection between the housing 1 and the magazine 2 is not easy. Moreover, in order to reduce instability after assembly, the conventional latching concavity 1b and latching convexity 2b are fit together with a minimum gap therebetween, and while having a certain length is preferred, if they are too long, connection becomes even more difficult.